The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional ep...The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional epoxy compatibilizer(Joncryl ADR-4368).The morphological,thermal,rheological,and mechanical properties of PEF/PA11 blends were investigated.Compared with neat PEF,the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two polymers.When Joncryl was incorporated into PEF/PA11 blends,the interfacial tension between PEF and PA11 was obviously reduced,reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy(SEM).The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend,which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular chains.Thus,the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of Joncryl.The compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1%and 30.3kJ/m2,respectively,compared with those of 3.6%and 3.8 kJ/m2 for neat PEF,respectively.This work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.展开更多
Long-chain polyamides(LCPAs)are a class of bio-based polymers that can bridge conventional polyolefins and polycondensates.In this work,taking the advantage of the amphiphilic nature of polyamide 1012(PA1012),membrane...Long-chain polyamides(LCPAs)are a class of bio-based polymers that can bridge conventional polyolefins and polycondensates.In this work,taking the advantage of the amphiphilic nature of polyamide 1012(PA1012),membranes were prepared by using a non-conventional phase separation approach,namely,mixed‘non-solvents’evaporation induced phase separation(MNEIPS).PA1012 can be dissolved in a mixture of polar and non-polar solvents,both of which are non-solvents of PA1012.During the sequential evaporation of the two solvents,the phase separation of PA1012 occurred,inducing the formation of porous structures.We investigated the process of membrane formation in detail,with a specific focus on the liquid-liquid and liquid-solid phase transitions involved.Moreover,we studied the influence of critical factors,such as polymer concentration and mixed-solvent ratio,on the morphologies and properties of PA1012 membranes.This study provides new insights into the development of porous materials based on long-chain polycondensates.展开更多
Carbon fibres have been produced from hydroxypropyl-modified lignin(TcC)/bio-based polyamide 1010(PA1010)blended filaments.Two grades of PA1010,with different molecular weights and rheological properties,were used for...Carbon fibres have been produced from hydroxypropyl-modified lignin(TcC)/bio-based polyamide 1010(PA1010)blended filaments.Two grades of PA1010,with different molecular weights and rheological properties,were used for blending with TcC.An oxidative thermal stabilisation step was used prior to carbonisation in an inert atmosphere to prevent the fusion of the filaments during the latter step.Thermal stabilisation was not possible using a one-step stabilisation process reported in the literature for lignin and other lignin/synthetic polymer blends.As a consequence,a cyclic process involving an additional isothermal phase at a lower temperature than the precursor filaments’melting point,was introduced to increase the cross-linking reactions between the lignin and polyamide.Thermally stabilised filaments were characterised by DSC,TGA,TGA-FTIR,ATR,and SEM techniques.Polymer rheology and heating rate used during thermal stabilisation influenced the thermal stabilisation process and mechanical properties of the derived filaments.Thermally stabilised filaments using optimised conditions(heating in the air atmosphere at 0.25℃/min to 180℃;isothermal for 1 h,cooling back down to ambient at 5℃/min;heating to 250℃ at 0.25℃/min,isothermal for 2 h)could be successfully carbonised.Carbon fibres pro-duced had void-free morphologies and mechanical properties comparable to similarly thermally stabilised and carbonised polyacrylonitrile(PAN)filaments.展开更多
The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed th...The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed the bio-based electrotechnical epoxy resins based on magnolol.High-performance epoxy resin(DGEMT)with a double crosslinked points and its composites(Al_(2)O_(3)/DGEMT)were obtained taking advantages of the two bifunctional groups(allyl and phenolic hydroxyl groups)of magnolol.Benefitting from the distinctive structure of DGEMT,the Al_(2)O_(3)/DGEMT composites exhibited the advantages of intrinsically high thermal conductivity,high insulation,and low dielectric loss.The AC breakdown strength and thermal conductivity of Al_(2)O_(3)/DGEMT composites were 35.5 kV/mm and 1.19 W·m-1·K-1,respectively,which were 15.6%and 52.6%higher than those of petroleum-based composites(Al_(2)O_(3)/DGEBA).And its dielectric loss tanδ=0.0046 was 20.7%lower than that of Al_(2)O_(3)/DGEBA.Furthermore,the mechanical,thermal and processing properties of Al_(2)O_(3)/DGEMT are fully comparable to those of Al_(2)O_(3)/DGEBA.This work confirms the feasibility of manufacturing environmentally friendly power equipment using bio-based epoxy resins,which has excellent engineering applications.展开更多
By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permea...By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permeability and heavy oil reservoirs under varying temperature conditions.The results demonstrate that this system effectively reduces oil–water interfacial tension,achieving an ultra-low interfacial tension state.The static oil washing efficiency of oil sands exceeds 85%,the average pressure reduction rate reaches 21.55%,and the oil recovery rate improves by 13.54%.These enhancements significantly increase the system’s ability to dissolve oilbased blockages,thereby lowering water injection pressure caused by organic fouling,increasing the injection volume of injection wells,and ultimately improving oil recovery efficiency.展开更多
In the context of transitioning toward more sustainable construction materials,this study explores the impact of incorporating millet husks as an alternative to sand on the physical,mechanical,and thermal performance ...In the context of transitioning toward more sustainable construction materials,this study explores the impact of incorporating millet husks as an alternative to sand on the physical,mechanical,and thermal performance of lightweight concrete.Through a mixture design approach,five formulations were selected and thoroughly characterized.The analysis of iso-response curves enabled an in-depth assessment of the cross-effects between formulation parameters and their interactions on the final properties of the material.The results show that integrating millet husks leads to a significant reduction in density,reaching up to 21%,while maintaining notable mechanical performance.A balanced formulation of sand and fibers achieved a maximum compressive strength of 12.11 MPa,demonstrating that,under specific conditions,plant fibers actively contribute to the structural integrity of the composite.In tensile strength,the positive influence of fibers is even more pronounced,with a maximum resistance of 8.62 MPa,highlighting their role in enhancing material cohesion.From a thermal perspective,millet husks reduce both thermal conductivity and effusivity,thereby limiting heat transfer and accumulation within the composite.Iso-response curve analysis reveals that these effects are directly linked to the proportions of the constituents and that achieving an optimal balance between sand,fibers,and cement is key to maximizing performance.These findings demonstrate that the adopted approach allows moving beyond conventional substitution methods by identifying optimal configurations for the design of lightweight bio-based concretes that are both strong and insulating,thereby confirming the potential of millet husks in developing lightweight concretes suitable for sustainable construction applications.展开更多
An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthrolin...An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthroline/bipyridine,and poly-F substituted phenyl ligands as the mixture linkers.The results of control experiments and theoretical calculations reveal that the–F on the phenyl linkers efficiently tunes the electron-deficient nature of Pd through the Zr_(6) clusters bridges,which favors the adsorption and activation of the furan ring.Furthermore,the conjugation of different nitrogen-containing ligands facilitates Pd coordination for the Heck-type insertion and subsequent electrophilic palladation,respectively.As a result,the oxidative arylation of FA derivatives is substantially enhanced because of these electronic and steric synergistic effects.Under the optimized conditions,72.2%FA conversion and 74.8%mono aryl furan(MAF)selectivity are shown in the Heck-type insertion.Meanwhile,85.3%of MAF is converted,affording 74.8%selectivity of final product(AFs)in the subsequent electrophilic palladation reaction.This process efficiency is remarkably higher than that with homogeneous catalysts.In addition,furan-benzene polymer obtained from the halogen-free synthesis catalyzed by UiO-67-Pd(F)show significantly better properties than that from conventional Suzuki coupling method.Therefore,the present work provides a new insight for useful AFs synthesis by oxidative arylation of bio-furan via rational tunning the metal center micro-environment of heterogeneous catalyst.展开更多
Novel bio-based and biodegradable block copolymers were synthesized by "click" reaction between poly(L-lactide)(PLLA) and polyamide 4(PA4). Upon tuning the molar mass of PLLA block, the properties of copolym...Novel bio-based and biodegradable block copolymers were synthesized by "click" reaction between poly(L-lactide)(PLLA) and polyamide 4(PA4). Upon tuning the molar mass of PLLA block, the properties of copolymers and electrospun ultrafine fibers were investigated and compared with those of PLLA and PA4 blends. PLLA and PA4 were found incompatible and formed individual crystalline regions, along with reciprocal inhibition in crystallization. Electrospun fibers were highly hydrophobic, even if hydrophilic PA4 was the rich component. The crystallinity of either PLLA or PA4 decreased after electrospinning and PLLA-rich as-spun fibers were almost amorphous. Immersion tests proved that fibers of block copolymers were relatively homogeneous with micro-phase separation between PLLA and PA4. The fibrous structures of copolymers were different from those of the fibers electrospun from blends, for which sheath-core structure induced by macro-phase separation between homopolymers of PLLA and PA4 was confirmed by TEM, EDS, and XPS.展开更多
This study aims to develop highly hygroscopic bio-based co-polyamides(CPs)by melt co-polycondensation of polyamide(PA)56 salt and PA66 salt with varying molar fractions.The functional groups and the chemical structure...This study aims to develop highly hygroscopic bio-based co-polyamides(CPs)by melt co-polycondensation of polyamide(PA)56 salt and PA66 salt with varying molar fractions.The functional groups and the chemical structure of the prepared samples were determined by Fourier transform infrared(FTIR)spectroscopy and proton nuclear magnetic resonance(^(1)H-NMR)spectroscopy.The relative viscosity was determined with an Ubbelohde viscometer.The melting behavior and the thermal stability of CPs were investigated by differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA).Furthermore,the water absorption behavior of CP hot-pressed film was studied.The results reveal that the melting point,the crystallization temperature and the crystallinity of CPs firstly decrease and then increase with the molar fraction of PA66 in CPs.The copolymerization of PA56 with PA66 leads to an obvious increase in water absorption.The CPs with PA66 molar fraction of 50%possess a high saturated water absorption rate of 17.6%,compared to 11.6%for pure PA56 and 7.8%for pure PA66.展开更多
Considerable progress has been made in recent years to the development of sustainable polymers from bio-based feedstocks.In this study,100%bio-based nylons were prepared via an integrated chemical and biological proce...Considerable progress has been made in recent years to the development of sustainable polymers from bio-based feedstocks.In this study,100%bio-based nylons were prepared via an integrated chemical and biological process from lignocellulose.These novel nylons were obtained by the melt polymerization of 3-propyladipic acid derived from lignin and 1,5-pentenediamine/1,4-butanediamine derived from carbohydrate sugar.Central to the concept is a three-step noble metal free catalytic chemical funnelling sequence(Raney Ni mediated reductive catalytic fractionation-reductive funnelling-oxidative funnelling),which allowed for obtaining a single component 3-propyladipic acid from lignin with high efficiency.The structural and thermodynamic properties of the obtained nylons have been systematically investigated,and thus obtained transparent bio-based nylons exhibited higher Mw(>32,000)and excellent thermal stability(Td5%>265℃).Considering their moderate Tg and good melt strength,these transparent bio-based nylons could serve as promising functional additives or temperature-responsive materials.展开更多
Microplastic pollution has become one of the most concerned focuses in the world.Among many treatment methods,photocatalysis is considered to be one of the most environmentally friendly methods.In this work,the photod...Microplastic pollution has become one of the most concerned focuses in the world.Among many treatment methods,photocatalysis is considered to be one of the most environmentally friendly methods.In this work,the photodegradation behavior of polyamide microplastics is studied by using polyamide 6(PA6)as model microplastics and FeCl_(3) as catalyst.It is hoped that the PA6 fiber can be effectively degraded by utilizing the strong oxidizing active species that can be produced after FeCl_(3) is irradiated in water.The results shows that PA6 fiber can be almost completely degraded after 10 days of irradiation in FeCl_(3) aqueous solution,indicating that it is promising to use this new method to solve the problem of PA6type microplastics.In addition,the chain scission mechanism and degradation process of PA6 are analyzed in detail by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS),which provides a new insight for the study of polymer degradation mechanism.展开更多
Side-by-side bicomponent fibers have a spring-like three-dimensional spiral crimp structure and are widely used in elastic fabric.The difference in thermal shrinkage between different polymers can produce an unbalance...Side-by-side bicomponent fibers have a spring-like three-dimensional spiral crimp structure and are widely used in elastic fabric.The difference in thermal shrinkage between different polymers can produce an unbalanced stress during the cooling process,and this unbalanced stress can be exploited to prepare naturally crimped fibers by spinning design.In this work,different types of polyamides(PAs)were selected for fabrication of the PA-based side-by-side bicomponent elastic fibers using melt spinning,and the structure development and performance of such bicomponent elastic fibers were studied.Meanwhile,thermoplastic PA elastomer(TPAE)with intrinsic elasticity was also used as one of the comparative materials.The block structure of the PA segment and the polyether segment in the TPAE molecule is the key to providing thermal shrinkage differences and forming a good interface structure.As a result,the crimp ratio of PA6/TPAE bicomponent elastic fiber is 7.23%,which is better than that of the currently commercialized T400 fiber(6.72%).The excellent crimp performance of PA6/TPAE bicomponent elastic fibers comes from the asymmetric distribution of the stress along the radial direction of the fibers during the cooling process,which is caused by the difference in thermal shrinkage between PA6 and TPAE.In addition,the crimp formability of the PA-based bicomponent elastic fibers could be improved by expanding the shrinkage stress through wet-heat treatment.The crimp ratio of PA6/TPAE bicomponent elastic fibers reaches the maximum(33.08%)after treatment at 100℃.At the same time,the fabric made of PA6/TPAE bicomponent elastic fibers has the excellent air and water vapor permeability,with an air permeability of 272.76 mm/s and a water vapor transmission rate of 406.71 g/(m^(2)·h).展开更多
Due to their extraordinary durability and thermal stability,Epoxy Resin Thermosets(ERTs)are essential in various industries.However,their poor recyclability leads to unacceptable environmental pollution.In this study,...Due to their extraordinary durability and thermal stability,Epoxy Resin Thermosets(ERTs)are essential in various industries.However,their poor recyclability leads to unacceptable environmental pollution.In this study,Wu et al.successfully synthesized a completely bio-based ERT using lignocellulose-derived building blocks which exhibit outstanding thermal and mechanical properties.Remarkably,these bio-materials degrade via methanolysis without the need of any catalyst,presenting a smart and cost-effective recycling strategy.Furthermore,this approach could be employed for fabricating reusable composites comprising glass fiber and plant fiber,thereby expanding its applications in sustainable transportation,coatings,paints or biomedical devices.展开更多
Toughening the petroleum-based epoxy resin blends with bio-based modifiers without compromising their modulus,mechanical strength,and other properties is still a big challenge in view of the sustainability.In this stu...Toughening the petroleum-based epoxy resin blends with bio-based modifiers without compromising their modulus,mechanical strength,and other properties is still a big challenge in view of the sustainability.In this study,a bio-based liquid crystal epoxy resin(THMT-E P)with an s-triazine ring structure was utilized to modify a petroleum-based bisphenol A epoxy resin(E51)with 4,4'-diaminodiphenylsulfone(DDS)as a curing agent,and the blended systems were evaluated for their thermal stability,mechanical properties,and flame retardancy.The results showed that the impact strength of the blended system initially increased and then decreased with the increase in THMT-EP content,and it reached the a maximum value of 26.5 kJ/m^(2)when the THMT-EP content was 5%,which was 31.2%higher than that of E51/DDS.Notably,the flexural strength,modulus,and glass transition tem perature of the blended system were all simultaneously improved with the addition of THMT-EP.At the same time,the addition of THMT-EP enhanced the flame retardancy of the system by increasing the char yield at 700℃and decreasing the peak heat release rate and total heat release rate.This work paves the way for a more sustainable improvement in the comprehensive performance of epoxy resin.展开更多
The pressing demand for sustainable advancements in road infrastructure has catalyzed extensive research into environmentally conscious alternatives for the maintenance and restoration of asphalt concrete pavements.Th...The pressing demand for sustainable advancements in road infrastructure has catalyzed extensive research into environmentally conscious alternatives for the maintenance and restoration of asphalt concrete pavements.This paper offers a comprehensive review and analysis of bio-based rejuvenators as a promising avenue for enhancing the longevity and sustainability of asphalt.Through a multifaceted exploration,it delves into various aspects of this innovative approach.Providing a thorough overview of bio-based rejuvenators,the study highlights their renewable and environmentally friendly characteristics.It conducts an in-depth examination of a wide spectrum of bio-derived materials,including vegetable oils,waste-derived bio-products,and biopolymers,through a comprehensive survey.The paper evaluates how bio-based rejuvenators enhance aged asphalt binders and mixes,effectively mitigating the adverse impacts of aging.Furthermore,it investigates how these rejuvenators address environmental concerns by identifying compatibility issues,assessing long-term performance,and evaluating economic feasibility.Finally,the paper outlines potential advancements and research pathways aimed at optimizing the utilization of bio-based rejuvenators in asphalt concrete,thereby contributing to the sustainable evolution of road infrastructure.展开更多
Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction conditions.In this work,t...Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction conditions.In this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 bar.Among them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst stability.Over the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst deactivation.The proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.展开更多
Zeolitic imidazolate framework-8(ZIF-8)is a typical filler used to fabricate mixed matrix membranes(MMMs)on account of its attractive advantage of high selective permeability for gas separation.However,the performance...Zeolitic imidazolate framework-8(ZIF-8)is a typical filler used to fabricate mixed matrix membranes(MMMs)on account of its attractive advantage of high selective permeability for gas separation.However,the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers,However,the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers,which will lead to a decrease of selectivity and the performance of gas separation will be strongly influenced.Herein,we modified ZIF-8 with 3-amino-1,2,4-triazole to obtain ZIF-8-NH_(2),Kapton polyamide acid was selected as the polymer matrix.Results showed that the ZIF-8-NH_(2)/Kapton MMMs has a good compatibility interface between ZIF-8 and Kapton because of the covalent bridging,even the filler loading up to 45%(mass).The 45%(mass)of ZIF-8-NH_(2)/Kapton membrane showed 297 barrer(1 barrer=10^(-10)10 cm^(3)·cm·cm^(-2)·s^(-1)·cmHg^(-1),1 cmHg=1333.22 Pa,standard temperature and pressure)of the permeability of H_(2)and 43.9 and 62.2 of selectivities for H_(2)/N_(2)and for H_(2)/CH_(4),respectively,which are beyond the upper limit of Robeson 2008.展开更多
Polyamide(PA)is a widely utilized engineering polymer,and its thermal and mechanical properties can be further improved by adding nanofillers.However,adding inorganic fullerene-like tungsten disulfide(IF-WS_(2))nanopa...Polyamide(PA)is a widely utilized engineering polymer,and its thermal and mechanical properties can be further improved by adding nanofillers.However,adding inorganic fullerene-like tungsten disulfide(IF-WS_(2))nanoparticles(NPs)to PA to produce composite precursor powders for additive manufacturing is challenging.Here,we report a novel and cost-effective method for fabricating PA-12 based nanocomposite(NC)powders with fixed/partially encapsulated IF-WS_(2) nanoparticulate fillers utilizing an advanced mixing technique because simple wet mixing(WM)can only attach fillers weakly to the powder surfaces when compared to the proposed method.The resulting nanocomposite powders maintained nearly the original particle size distribution of PA-12.They also exhibited improved rheological properties,melting,and crystallization behaviors compared with those prepared by the WM method.The laser-sintered PA-12 nanocomposite specimens revealed enhanced pow-der thermal stability and higher tensile strengths than pristine PA-12,validating the advantages of the novel technique for the fabrication of polyamide nanocomposite powders and their suitability for utilization in laser sintering additive manufacturing.These results demonstrate that high-performance engineered PA-12 nanocom-posite components can be directly laser sintered,and this technique can potentially be extended to fabricate other engineered polymeric nanocomposite powders.展开更多
An improved method for preparing melamine cyanurate (MCA) based flame retardant polyamide 6 (FRPA6) materials has been proposed. This processing method, i.e., improved in situ polymerization, was used to synthesiz...An improved method for preparing melamine cyanurate (MCA) based flame retardant polyamide 6 (FRPA6) materials has been proposed. This processing method, i.e., improved in situ polymerization, was used to synthesize flame retardant PA6. In situ formed MCA nanoparticles were supposed to be linked to PA6 chains in the ε-caprolactam hydrolytic polymerization system to obtain startype polymers for the first time. Through TEM photographs, it can be found that the in situ formed MCA nanoparticles with diametric size of less than 50 nm, are nanoscaled, highly uniformly dispersed in the PA6 matrix. Synthesized flame retardant PA6 have good fire performance which can achieve UL-94 V-0 rating at 1.6 mm thickness with the presence of 7.34 wt.% MCA in the matrix.展开更多
Polyamide 6 underwent an efficient depolymerization in hydrophilic ionic liquids under microwave irradiation at 300C. The depolymerization completed within 60 min. Caprolactam was readily separated by simple extractio...Polyamide 6 underwent an efficient depolymerization in hydrophilic ionic liquids under microwave irradiation at 300C. The depolymerization completed within 60 min. Caprolactam was readily separated by simple extraction procedure and the ionic liquids were recovered and reused for several times. Addition of catalytic amounts of DMAP(N,N-dimethylaminopyridine) promoted the depolymerization effectively.The present improved procedure provides a method to avoid direct distillation procedure, which consumes energy for the separation of caprolactam from ionic liquids. Although some contamination of ionic liquids was observed, the present procedure provides a new possibility for the use of ionic liquids for plastic chemical recycling from the viewpoint of development of an energy-saving methodology. Use of solubility switchable ionic liquids is also examined to explore a possibility for better separation although depolymerization did not work well.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(No.51803224).
文摘The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional epoxy compatibilizer(Joncryl ADR-4368).The morphological,thermal,rheological,and mechanical properties of PEF/PA11 blends were investigated.Compared with neat PEF,the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two polymers.When Joncryl was incorporated into PEF/PA11 blends,the interfacial tension between PEF and PA11 was obviously reduced,reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy(SEM).The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend,which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular chains.Thus,the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of Joncryl.The compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1%and 30.3kJ/m2,respectively,compared with those of 3.6%and 3.8 kJ/m2 for neat PEF,respectively.This work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.
基金supported by the Fundamental Research Funds for the Central Universities(No.2023ZYGXZR107)the TCL Science and Technology Innovation Fund。
文摘Long-chain polyamides(LCPAs)are a class of bio-based polymers that can bridge conventional polyolefins and polycondensates.In this work,taking the advantage of the amphiphilic nature of polyamide 1012(PA1012),membranes were prepared by using a non-conventional phase separation approach,namely,mixed‘non-solvents’evaporation induced phase separation(MNEIPS).PA1012 can be dissolved in a mixture of polar and non-polar solvents,both of which are non-solvents of PA1012.During the sequential evaporation of the two solvents,the phase separation of PA1012 occurred,inducing the formation of porous structures.We investigated the process of membrane formation in detail,with a specific focus on the liquid-liquid and liquid-solid phase transitions involved.Moreover,we studied the influence of critical factors,such as polymer concentration and mixed-solvent ratio,on the morphologies and properties of PA1012 membranes.This study provides new insights into the development of porous materials based on long-chain polycondensates.
文摘Carbon fibres have been produced from hydroxypropyl-modified lignin(TcC)/bio-based polyamide 1010(PA1010)blended filaments.Two grades of PA1010,with different molecular weights and rheological properties,were used for blending with TcC.An oxidative thermal stabilisation step was used prior to carbonisation in an inert atmosphere to prevent the fusion of the filaments during the latter step.Thermal stabilisation was not possible using a one-step stabilisation process reported in the literature for lignin and other lignin/synthetic polymer blends.As a consequence,a cyclic process involving an additional isothermal phase at a lower temperature than the precursor filaments’melting point,was introduced to increase the cross-linking reactions between the lignin and polyamide.Thermally stabilised filaments were characterised by DSC,TGA,TGA-FTIR,ATR,and SEM techniques.Polymer rheology and heating rate used during thermal stabilisation influenced the thermal stabilisation process and mechanical properties of the derived filaments.Thermally stabilised filaments using optimised conditions(heating in the air atmosphere at 0.25℃/min to 180℃;isothermal for 1 h,cooling back down to ambient at 5℃/min;heating to 250℃ at 0.25℃/min,isothermal for 2 h)could be successfully carbonised.Carbon fibres pro-duced had void-free morphologies and mechanical properties comparable to similarly thermally stabilised and carbonised polyacrylonitrile(PAN)filaments.
基金supported by the China Postdoctoral Science Foundation(No.2023M743622)Natural Science Foundation of Ningbo City(No.2024J109)+2 种基金National Natural Science Foundation of China(Nos.E52307038 and U23A20589)Ningbo 2025 Key Scientific Research Programs(Nos.2022Z111,2022Z160 and 2022Z198)the Leading Innovativeand Entrepreneur Team Introduction Program of Zhejiang(No.2021R01005).
文摘The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed the bio-based electrotechnical epoxy resins based on magnolol.High-performance epoxy resin(DGEMT)with a double crosslinked points and its composites(Al_(2)O_(3)/DGEMT)were obtained taking advantages of the two bifunctional groups(allyl and phenolic hydroxyl groups)of magnolol.Benefitting from the distinctive structure of DGEMT,the Al_(2)O_(3)/DGEMT composites exhibited the advantages of intrinsically high thermal conductivity,high insulation,and low dielectric loss.The AC breakdown strength and thermal conductivity of Al_(2)O_(3)/DGEMT composites were 35.5 kV/mm and 1.19 W·m-1·K-1,respectively,which were 15.6%and 52.6%higher than those of petroleum-based composites(Al_(2)O_(3)/DGEBA).And its dielectric loss tanδ=0.0046 was 20.7%lower than that of Al_(2)O_(3)/DGEBA.Furthermore,the mechanical,thermal and processing properties of Al_(2)O_(3)/DGEMT are fully comparable to those of Al_(2)O_(3)/DGEBA.This work confirms the feasibility of manufacturing environmentally friendly power equipment using bio-based epoxy resins,which has excellent engineering applications.
文摘By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permeability and heavy oil reservoirs under varying temperature conditions.The results demonstrate that this system effectively reduces oil–water interfacial tension,achieving an ultra-low interfacial tension state.The static oil washing efficiency of oil sands exceeds 85%,the average pressure reduction rate reaches 21.55%,and the oil recovery rate improves by 13.54%.These enhancements significantly increase the system’s ability to dissolve oilbased blockages,thereby lowering water injection pressure caused by organic fouling,increasing the injection volume of injection wells,and ultimately improving oil recovery efficiency.
文摘In the context of transitioning toward more sustainable construction materials,this study explores the impact of incorporating millet husks as an alternative to sand on the physical,mechanical,and thermal performance of lightweight concrete.Through a mixture design approach,five formulations were selected and thoroughly characterized.The analysis of iso-response curves enabled an in-depth assessment of the cross-effects between formulation parameters and their interactions on the final properties of the material.The results show that integrating millet husks leads to a significant reduction in density,reaching up to 21%,while maintaining notable mechanical performance.A balanced formulation of sand and fibers achieved a maximum compressive strength of 12.11 MPa,demonstrating that,under specific conditions,plant fibers actively contribute to the structural integrity of the composite.In tensile strength,the positive influence of fibers is even more pronounced,with a maximum resistance of 8.62 MPa,highlighting their role in enhancing material cohesion.From a thermal perspective,millet husks reduce both thermal conductivity and effusivity,thereby limiting heat transfer and accumulation within the composite.Iso-response curve analysis reveals that these effects are directly linked to the proportions of the constituents and that achieving an optimal balance between sand,fibers,and cement is key to maximizing performance.These findings demonstrate that the adopted approach allows moving beyond conventional substitution methods by identifying optimal configurations for the design of lightweight bio-based concretes that are both strong and insulating,thereby confirming the potential of millet husks in developing lightweight concretes suitable for sustainable construction applications.
文摘An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthroline/bipyridine,and poly-F substituted phenyl ligands as the mixture linkers.The results of control experiments and theoretical calculations reveal that the–F on the phenyl linkers efficiently tunes the electron-deficient nature of Pd through the Zr_(6) clusters bridges,which favors the adsorption and activation of the furan ring.Furthermore,the conjugation of different nitrogen-containing ligands facilitates Pd coordination for the Heck-type insertion and subsequent electrophilic palladation,respectively.As a result,the oxidative arylation of FA derivatives is substantially enhanced because of these electronic and steric synergistic effects.Under the optimized conditions,72.2%FA conversion and 74.8%mono aryl furan(MAF)selectivity are shown in the Heck-type insertion.Meanwhile,85.3%of MAF is converted,affording 74.8%selectivity of final product(AFs)in the subsequent electrophilic palladation reaction.This process efficiency is remarkably higher than that with homogeneous catalysts.In addition,furan-benzene polymer obtained from the halogen-free synthesis catalyzed by UiO-67-Pd(F)show significantly better properties than that from conventional Suzuki coupling method.Therefore,the present work provides a new insight for useful AFs synthesis by oxidative arylation of bio-furan via rational tunning the metal center micro-environment of heterogeneous catalyst.
基金financially supported by the National Key Research and Development Program of China (Nos. 2017YFB0309301 and 2017YFB0309302)the Natural Science Foundation of Shanghai, China (No. 17ZR1407200)
文摘Novel bio-based and biodegradable block copolymers were synthesized by "click" reaction between poly(L-lactide)(PLLA) and polyamide 4(PA4). Upon tuning the molar mass of PLLA block, the properties of copolymers and electrospun ultrafine fibers were investigated and compared with those of PLLA and PA4 blends. PLLA and PA4 were found incompatible and formed individual crystalline regions, along with reciprocal inhibition in crystallization. Electrospun fibers were highly hydrophobic, even if hydrophilic PA4 was the rich component. The crystallinity of either PLLA or PA4 decreased after electrospinning and PLLA-rich as-spun fibers were almost amorphous. Immersion tests proved that fibers of block copolymers were relatively homogeneous with micro-phase separation between PLLA and PA4. The fibrous structures of copolymers were different from those of the fibers electrospun from blends, for which sheath-core structure induced by macro-phase separation between homopolymers of PLLA and PA4 was confirmed by TEM, EDS, and XPS.
基金National Key Research and Development Program of China(No.2017YFB0309400).
文摘This study aims to develop highly hygroscopic bio-based co-polyamides(CPs)by melt co-polycondensation of polyamide(PA)56 salt and PA66 salt with varying molar fractions.The functional groups and the chemical structure of the prepared samples were determined by Fourier transform infrared(FTIR)spectroscopy and proton nuclear magnetic resonance(^(1)H-NMR)spectroscopy.The relative viscosity was determined with an Ubbelohde viscometer.The melting behavior and the thermal stability of CPs were investigated by differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA).Furthermore,the water absorption behavior of CP hot-pressed film was studied.The results reveal that the melting point,the crystallization temperature and the crystallinity of CPs firstly decrease and then increase with the molar fraction of PA66 in CPs.The copolymerization of PA56 with PA66 leads to an obvious increase in water absorption.The CPs with PA66 molar fraction of 50%possess a high saturated water absorption rate of 17.6%,compared to 11.6%for pure PA56 and 7.8%for pure PA66.
基金support by National Key Research and Development Program of China(Grant No.:2023YFA0913604)Program of National Natural Science Foundation of China(Grant No.:22178170,22378195)+2 种基金Six talent peaks project in Jiangsu Province(SWYY-045)Program of National Natural Science Foundation of China(Grant No.22208155)Jiangsu Province Natural Science Foundation for Young Scholars(Grant No.BK20210552).
文摘Considerable progress has been made in recent years to the development of sustainable polymers from bio-based feedstocks.In this study,100%bio-based nylons were prepared via an integrated chemical and biological process from lignocellulose.These novel nylons were obtained by the melt polymerization of 3-propyladipic acid derived from lignin and 1,5-pentenediamine/1,4-butanediamine derived from carbohydrate sugar.Central to the concept is a three-step noble metal free catalytic chemical funnelling sequence(Raney Ni mediated reductive catalytic fractionation-reductive funnelling-oxidative funnelling),which allowed for obtaining a single component 3-propyladipic acid from lignin with high efficiency.The structural and thermodynamic properties of the obtained nylons have been systematically investigated,and thus obtained transparent bio-based nylons exhibited higher Mw(>32,000)and excellent thermal stability(Td5%>265℃).Considering their moderate Tg and good melt strength,these transparent bio-based nylons could serve as promising functional additives or temperature-responsive materials.
基金supported by the Natural Science Foundation of Zhejiang Province(No.LDQ23E030001)。
文摘Microplastic pollution has become one of the most concerned focuses in the world.Among many treatment methods,photocatalysis is considered to be one of the most environmentally friendly methods.In this work,the photodegradation behavior of polyamide microplastics is studied by using polyamide 6(PA6)as model microplastics and FeCl_(3) as catalyst.It is hoped that the PA6 fiber can be effectively degraded by utilizing the strong oxidizing active species that can be produced after FeCl_(3) is irradiated in water.The results shows that PA6 fiber can be almost completely degraded after 10 days of irradiation in FeCl_(3) aqueous solution,indicating that it is promising to use this new method to solve the problem of PA6type microplastics.In addition,the chain scission mechanism and degradation process of PA6 are analyzed in detail by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS),which provides a new insight for the study of polymer degradation mechanism.
基金Fundamental Research Funds for the Central Universities of China(No.2232022D-10)Open Fund of State Key Laboratory of Biobased Fiber Manufacturing Technology,China(No.SKL202306)。
文摘Side-by-side bicomponent fibers have a spring-like three-dimensional spiral crimp structure and are widely used in elastic fabric.The difference in thermal shrinkage between different polymers can produce an unbalanced stress during the cooling process,and this unbalanced stress can be exploited to prepare naturally crimped fibers by spinning design.In this work,different types of polyamides(PAs)were selected for fabrication of the PA-based side-by-side bicomponent elastic fibers using melt spinning,and the structure development and performance of such bicomponent elastic fibers were studied.Meanwhile,thermoplastic PA elastomer(TPAE)with intrinsic elasticity was also used as one of the comparative materials.The block structure of the PA segment and the polyether segment in the TPAE molecule is the key to providing thermal shrinkage differences and forming a good interface structure.As a result,the crimp ratio of PA6/TPAE bicomponent elastic fiber is 7.23%,which is better than that of the currently commercialized T400 fiber(6.72%).The excellent crimp performance of PA6/TPAE bicomponent elastic fibers comes from the asymmetric distribution of the stress along the radial direction of the fibers during the cooling process,which is caused by the difference in thermal shrinkage between PA6 and TPAE.In addition,the crimp formability of the PA-based bicomponent elastic fibers could be improved by expanding the shrinkage stress through wet-heat treatment.The crimp ratio of PA6/TPAE bicomponent elastic fibers reaches the maximum(33.08%)after treatment at 100℃.At the same time,the fabric made of PA6/TPAE bicomponent elastic fibers has the excellent air and water vapor permeability,with an air permeability of 272.76 mm/s and a water vapor transmission rate of 406.71 g/(m^(2)·h).
基金the foundational support by the Fundamental Research Funds for the Central Universities(BLX202132)the foundational support by the Beijing Youth Talent Funding Program-Visiting program for young foreign scholars(Q2023043)IIT(BHU)Varanasi.
文摘Due to their extraordinary durability and thermal stability,Epoxy Resin Thermosets(ERTs)are essential in various industries.However,their poor recyclability leads to unacceptable environmental pollution.In this study,Wu et al.successfully synthesized a completely bio-based ERT using lignocellulose-derived building blocks which exhibit outstanding thermal and mechanical properties.Remarkably,these bio-materials degrade via methanolysis without the need of any catalyst,presenting a smart and cost-effective recycling strategy.Furthermore,this approach could be employed for fabricating reusable composites comprising glass fiber and plant fiber,thereby expanding its applications in sustainable transportation,coatings,paints or biomedical devices.
基金financially supported by the National Natural Science Foundation of China(Nos.52073038 and 51873027)the Fundamental Research Funds for the Central Universities(No.DUT22LAB605)。
文摘Toughening the petroleum-based epoxy resin blends with bio-based modifiers without compromising their modulus,mechanical strength,and other properties is still a big challenge in view of the sustainability.In this study,a bio-based liquid crystal epoxy resin(THMT-E P)with an s-triazine ring structure was utilized to modify a petroleum-based bisphenol A epoxy resin(E51)with 4,4'-diaminodiphenylsulfone(DDS)as a curing agent,and the blended systems were evaluated for their thermal stability,mechanical properties,and flame retardancy.The results showed that the impact strength of the blended system initially increased and then decreased with the increase in THMT-EP content,and it reached the a maximum value of 26.5 kJ/m^(2)when the THMT-EP content was 5%,which was 31.2%higher than that of E51/DDS.Notably,the flexural strength,modulus,and glass transition tem perature of the blended system were all simultaneously improved with the addition of THMT-EP.At the same time,the addition of THMT-EP enhanced the flame retardancy of the system by increasing the char yield at 700℃and decreasing the peak heat release rate and total heat release rate.This work paves the way for a more sustainable improvement in the comprehensive performance of epoxy resin.
基金the Swedish Research Council for Sustainable Development FORMAS(grant 2021-00527)Wangjie Wu acknowledges the scholarship funding of the CSC-KTH program.
文摘The pressing demand for sustainable advancements in road infrastructure has catalyzed extensive research into environmentally conscious alternatives for the maintenance and restoration of asphalt concrete pavements.This paper offers a comprehensive review and analysis of bio-based rejuvenators as a promising avenue for enhancing the longevity and sustainability of asphalt.Through a multifaceted exploration,it delves into various aspects of this innovative approach.Providing a thorough overview of bio-based rejuvenators,the study highlights their renewable and environmentally friendly characteristics.It conducts an in-depth examination of a wide spectrum of bio-derived materials,including vegetable oils,waste-derived bio-products,and biopolymers,through a comprehensive survey.The paper evaluates how bio-based rejuvenators enhance aged asphalt binders and mixes,effectively mitigating the adverse impacts of aging.Furthermore,it investigates how these rejuvenators address environmental concerns by identifying compatibility issues,assessing long-term performance,and evaluating economic feasibility.Finally,the paper outlines potential advancements and research pathways aimed at optimizing the utilization of bio-based rejuvenators in asphalt concrete,thereby contributing to the sustainable evolution of road infrastructure.
基金support from European Union Seventh Frame-work Programme(FP7/2007-2013 project SusFuelCat,grant No.310490)is acknowledged.
文摘Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction conditions.In this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 bar.Among them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst stability.Over the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst deactivation.The proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.
基金funded by National Natural Science Foundation of China(22278023)Beijing Municipal Science and Technology Planning Project(Z221100002722002)+1 种基金Beijing Natural Science Foundation(2222015)the long-term from the Ministry of Finance and the Ministry of Education of China.
文摘Zeolitic imidazolate framework-8(ZIF-8)is a typical filler used to fabricate mixed matrix membranes(MMMs)on account of its attractive advantage of high selective permeability for gas separation.However,the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers,However,the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers,which will lead to a decrease of selectivity and the performance of gas separation will be strongly influenced.Herein,we modified ZIF-8 with 3-amino-1,2,4-triazole to obtain ZIF-8-NH_(2),Kapton polyamide acid was selected as the polymer matrix.Results showed that the ZIF-8-NH_(2)/Kapton MMMs has a good compatibility interface between ZIF-8 and Kapton because of the covalent bridging,even the filler loading up to 45%(mass).The 45%(mass)of ZIF-8-NH_(2)/Kapton membrane showed 297 barrer(1 barrer=10^(-10)10 cm^(3)·cm·cm^(-2)·s^(-1)·cmHg^(-1),1 cmHg=1333.22 Pa,standard temperature and pressure)of the permeability of H_(2)and 43.9 and 62.2 of selectivities for H_(2)/N_(2)and for H_(2)/CH_(4),respectively,which are beyond the upper limit of Robeson 2008.
基金supported by National Natural Science Foundation(Grant.Nos.12205056,51972068)Natural Science Foundation of Guangxi Province in China(Grant.No.2021GXNSFBA076003)the UK Engineering and Physical Science Research Council(EPSRC)for funding(EPSRC Grant:Novel high-performance polymeric composite materials for additive manufacturing of multifunctional components,EP/N034627/1).
文摘Polyamide(PA)is a widely utilized engineering polymer,and its thermal and mechanical properties can be further improved by adding nanofillers.However,adding inorganic fullerene-like tungsten disulfide(IF-WS_(2))nanoparticles(NPs)to PA to produce composite precursor powders for additive manufacturing is challenging.Here,we report a novel and cost-effective method for fabricating PA-12 based nanocomposite(NC)powders with fixed/partially encapsulated IF-WS_(2) nanoparticulate fillers utilizing an advanced mixing technique because simple wet mixing(WM)can only attach fillers weakly to the powder surfaces when compared to the proposed method.The resulting nanocomposite powders maintained nearly the original particle size distribution of PA-12.They also exhibited improved rheological properties,melting,and crystallization behaviors compared with those prepared by the WM method.The laser-sintered PA-12 nanocomposite specimens revealed enhanced pow-der thermal stability and higher tensile strengths than pristine PA-12,validating the advantages of the novel technique for the fabrication of polyamide nanocomposite powders and their suitability for utilization in laser sintering additive manufacturing.These results demonstrate that high-performance engineered PA-12 nanocom-posite components can be directly laser sintered,and this technique can potentially be extended to fabricate other engineered polymeric nanocomposite powders.
文摘An improved method for preparing melamine cyanurate (MCA) based flame retardant polyamide 6 (FRPA6) materials has been proposed. This processing method, i.e., improved in situ polymerization, was used to synthesize flame retardant PA6. In situ formed MCA nanoparticles were supposed to be linked to PA6 chains in the ε-caprolactam hydrolytic polymerization system to obtain startype polymers for the first time. Through TEM photographs, it can be found that the in situ formed MCA nanoparticles with diametric size of less than 50 nm, are nanoscaled, highly uniformly dispersed in the PA6 matrix. Synthesized flame retardant PA6 have good fire performance which can achieve UL-94 V-0 rating at 1.6 mm thickness with the presence of 7.34 wt.% MCA in the matrix.
基金partially supported by the Grant-inAid for Scientific Research A(24241023)Grant-in-Aid for Challenging Exploratory Research(17K19139)from the Japan Society for the Promotion of Science
文摘Polyamide 6 underwent an efficient depolymerization in hydrophilic ionic liquids under microwave irradiation at 300C. The depolymerization completed within 60 min. Caprolactam was readily separated by simple extraction procedure and the ionic liquids were recovered and reused for several times. Addition of catalytic amounts of DMAP(N,N-dimethylaminopyridine) promoted the depolymerization effectively.The present improved procedure provides a method to avoid direct distillation procedure, which consumes energy for the separation of caprolactam from ionic liquids. Although some contamination of ionic liquids was observed, the present procedure provides a new possibility for the use of ionic liquids for plastic chemical recycling from the viewpoint of development of an energy-saving methodology. Use of solubility switchable ionic liquids is also examined to explore a possibility for better separation although depolymerization did not work well.